Grinding apparatus for plate glass



Oct- 13, 1925- J. SODERBERG GRINDING APPARATUS FOR PLATE GLASS 3 Sheets Sheet 1 Filed July 2 1923 /NVEN70R Oct. 13,1925.

J. SODERBERG GRINDING APPARATUS FOR FLAT 5 GLASS s Sheets-Sheet 2 Filed July 29 FII3.Z-

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a ma 7. 1 J U J. SODERBERG GRINDiNG APPARATUS FOR PLATE GLASS Filed July 2 1923 3 Sheets-Sheet 5 F'll3.E

Patented Oct. 13, 1925.

UNITED STATES 1,556,730 PATENT OFFICE.

moon sonuannne, or rrr'rsauaen, PENNSYLVANIA, assreuoi 'ro nrrsauaea rum: omss comm, a coaroauron or rmmsvnvma.

enmnme mmrus non 2mm emss.

Application filed July 28, 1923. Serial 110. 854,477.

To all whom it may concern:

Be it known that I, JACOB SODERBERG, a citizen of the United States, and a resident of Pittsbur h, in the county of Allegheny 6 and State Pennsylvania, have made a new and useful invention in Improvements in Grinding Apparatus for Plate Glass, of which the following is a specification.

The invention relates to grinding appa-, l0 ratus for plate glass and particularly to apparatus for use in a straightaway operation in which the glass is carried in a continuous sheet or ribbon or in a series of sheets upon tables or carriers beneath a series of grind- 15 ing machines. The invention has for its principal object the provision of improved means for grading and supplying abrasive to the system involving the series ,of grinding machines as above specified, such means 20 being arranged so that abrasive of the proper degree of fineness may be supplled to all the various machines, and so that a high degree of economy in the use of the abrasive is secured. One embodiment of the 25 invention is illustrated in the accompanying drawings wherein:

Figure 1 is a plan view of the apparatus. Figs. 2 and 3 are sections on the lines IIII and IIIIII respectively of Fig. 1.

30 Fig. 4 is an'enlarged detail section through the syphon outlet at the top of one of the tanks. Fig. 5 is an enlarged section through the outlet at the top of the first grade tank of the series. And Figs. 6 and 7 are detail views showing the scraper or squeegee used intermediate the various grinding tables.

Referrin to the drawings, 1 to are a series of grinding machines arranged insets of five, the first set, 1 to 5, being supplied from a grading tank 16, the second set, 6 to 10, being supplied with abrasive fromthetank 17- and the third set, 11 to 15, being sup lied with abrasive from the gradin tan 18. The inding machines are'pre erably ofthe type illustrated in Figs. 2 and 3, comprising a runner 19 carried by a shaft 20 driven from a motor 21 through the intermediary of reduction gearing in the casing 22. The runner and its driving mechanism is supported for vertical movement upon a lever 23 whose position is controlled by means of the rod 24 which is threaded at its lower end and worked up.

and down by means of a nut 25 provided with a suitable hand wheel. This particular sump. The sump itsel are designed to perform the rough grind form of grinding machine constitutes no part of mv invention, as any other type -might be substituted. Extending beneath the series of machines are the tracks 26 upon which are mounted a series of cars 27 carrying upon their upper sides the sheets of glass which are to be ground. These cars are carried along beneath the series of grindmg runners at a uniform speed by an suitable form of mechanism. The trac s are preferably mounted upon a concrete foundation 28 which is formed so as to rovide splash walls 29 at the sides of the ta 1e and suitable drainage ditches 30 whereby the used abrasive and water from the cars or tables may be returned to the sumps beneath the grading tanks. I

The grading tank 16 is referabl of the conical form indicated in ig. 2 an is supplied from a sump 30 by means of apump 31 having the inlet 32 projecting into the is supplied with green or new sand from time to time from the elevated bin 33 provided with an outlet 23 leading into the sump, and the bin itself 1s supplied with sand, either by means of an overhead bucket arrangement, or by means of the elevator 34 adapted to raise the sand from the pit 35.

Since the first five machines of the series operation, it is not necessary that the san should be separated into difl'erent grades for these machines, so that all the abrasive for these five machines is taken from the same levelin the grading tank 16. by means of the 36. which discharges into a box 37 from w ich the pi s 38 lead to the various runners and dlscharge to the openings 39 throu h the centers thereof. The box 37 is provi ed with an overflow com artment 40 (Fig. 5) and the ipe 41 from t is overflow leads back into the sump 30. L In order to control the flow through the various pipes 38, the ball valves 42 are preferably employed, such valves being moved up and down by means of the chains 43. In order to agitate the mixture of sand and water in the compartment 37 a supplemental pipe 44 leadin from the water main and havm a controlling valve 45 may be employed. 'Fhe tank is also provided with an overflow 46,

the surplus water may be carried to the T drain 47 leading from the ditch beneath the "tables to the sump 48 of the next grading tank 17.

By reason of the conical form of the tank 16, the velocity of the water decreases from the lower end of the conical portion to the u per portion, and by adjusting the speed 0? the pump 31 the pipe 36 will withdraw only the coarsest abrasive, the finer abrasive rising above the lower end of the pipe and discharging through the outlet 46 for use in the next tank in which finer grades of sand are required- The used sand from the first five tables together with the surplus water is discharged into the drain 47 leading to the sump 48 from which the grading tank 17 is supplied. This grading tank is also of conical form as indicated in Fig. 3 and is supplied from the sump by means of the pump 49 through the pipe 50. The contents of the tank is withdrawn through the pi s 51, 52, 53, 54 and 55, all leading from di erent levels in the tank as illustrated in Fig. 3. The abrasive withdrawn from the pipe 51 is the coarsest and this is conducted to machine 6, the abrasive from the pipes 52 to 55 being successively finer and being conducted to the machines 7, 8, 9 and 10. The

material is withdrawn from the pipes 51 to 55 by means of the. syphon arrangement shown in Fig. 4, the pipe 53 as'here shown extending through the side of the tank to the downwardly extending pipe 56 which carries on its lower end the sleeve57, adjustable vertically and held in position by means of the set screw 58. The sleeve discharges into a funnel 59 carried by the u per end of one of the series of pipes 60 w ich'lead to the grinding table. The use of the sleeve 57 permits of the ad'ustment of the head upon the liquid disc arging through the syphon so that the velocity of flow may be controlled to suit re uirements. Additional water may be supp ied to the ipe 56 to agitate the ixture by means of the small water pipe 61. The overflow from this tank passes through the pipe 62 to the drain 63 leading to the sump 64 of the third grading tank of the series, so that the excess water and abrasive too fine for use are carried on to the next set of machines which require the finest sand. The sand which. collects in this tank 17 which is too coarse for use in the machines supplied'b the tank is returned to the sump of the tan 16 by means of a pipe 65 leading from a point below the lower end of the lowest pipe 15.

The last five grinding machines 11 to 15 are supplied from the tank 18 by means of the i s 66 which are fed from syphon pipes ending to difierent levels in the tank .18, the same as in tank 17, this tank also bemg conical and being arranged throughout the same as. tank 16 except that the angle between the sides of the cone is preferably more acute. The sump 64 is supplied with abrasive and water by means of the drain 63 leading from the ditch of the grinding machines. This tank 18 is also provided with an overflow 67 by means of which the sand too fine for'use and the mud may be discharged to the settling pit 68, which settling pit also receives the dis charge from the drain 69 at the end of the series of, machines 11 to 15. This settling pit is provided with an overflow 7 0 leading to the sewer and also with a water return pipe 71 leading back to the sump 30 of the first tank 16 so that there will be no unnecessary waste of water. The tank 18 is also provided with a pipe 72 corresponding to the pipe 65 described in connection with the tank 16 and serving to return the abrasive which collects in the tank 18 which is too coarse for use to the sump 48 of the tank 17. The pipes 72 and 65, thus serves to relieve the tanks 18 and 17 of abrasive too coarse for use in such tanks, which abrasive might otherwise collect tosuch an extent that it would modify the velocit of flow throu h the tanks, thus chan 'nglt e character of abrasive discharged t rough the syphon pipes. This also involves economy as the abrasive which is too coarse for use in one tank is carried back and used in the tank next preceding in which it may be utilized.

In order to prevent the sand-used with the machines 1 to 5 passin along with the tables to the machines of t e next series, a squeegee device or scraper 73 is em loyed between machines 5 and 6. Similar evices 74, 75, etc. are provided between all of the machines following 6, the purpose being to prevent sand, which is too coarse, from being carried along, as such sand tends to scratch the glass and retard the smoothing e ration. This scraper device is prefera ly of the construction illustrated in Figs. 6 and 7, consisting of a pair of inclined frame members 76 to which are secured the rubber sheets 77 bearing at their ed s upon the surface of the glass 78. The on of the members 76 are turned forwardly as indi cated at 79 and are pivoted at 80 to suitable brackets carried upon the splash walls extending along the drains 30. Any other suitable means might be employed for. accomplishing this function.

e operation of the a paratus will readily ap arent from the oregoing. of'the tanks 16, 17 and 18 sup lies its set of machines with difi'erent gr es of abrasive gradually tapering oi! from the coarsest grade whlch is supplied to the machines 1 to 5 to the finest grades which are supplied to the last set of machines 11 to 15, the machine 15' receiving the very finest sand preliminary to r the application of emery or some finer material for the smoothing operation; It will be understood that the invention is not limited to the use of any particular number of grinding machines and that the number of machines in each set supplied from a single grading tank may be varied to meet requirements.

turned to the preceding tank so that there is no loss of this coarse material and it is eliminated from the tank in which it might otherwise cause interference with the finer grades. Finally the surplus water from the settling pit and any line sand which might be useful in the tank 16 is returned through the pipe 71 to the sump of the tank 16 and eventually finds its way back again to tank 16 for reuse. The system is thus made economical throughout, the only sand which is discharged to the sewer being that which is too fine for use in any of thetanks.

i Vhat I claim is:

1. In combination in grinding apparatus, a series of sets of grinding machines, means for carrying sheet glass continuously beneath the series of machines, a series of grading tanks, one for each set of machines, means for causing an upward fiow of liquid through each of the tanks to grade the abrasive therein, means for supplyingthe graded abrasive from each tank to its set of grinding machines, and means for supplying the used abrasive and water from the first set of grinding machines to the tank for the next set of machines.

2. In combination in grinding apparatus, a series of sets of grinding machines, means for carrying sheet glass continuously be neath the series of machines, a, series of grading tanks, one ioreach set of machines,

means for causing an upward flow of liquidthrough each of the tanks to rade the abrasive therein, means for supp ying the graded abrasive from each tank to its set of grinding machines, 'means for supplyill)- ing the grades too fine for use in the first grading tank in the series to the second grading tank for supplying the second set,

of machines, and means for supplying the used abrasive and Water from the first set of grinding machines to said second grading tank. I

3. In combination in grindin apparatus, a series of sets of grinding mac ines, means for carrying sheet glass continuously be neath the series of machines, a series of grading tanks, one for each set of machines, means for causing an upward flow of liquid through each of the tanks to grade the abrasive therein, means for supplying the graded abrasive from each tank to its set of grinding machines, and means for supplying the used abrasive and Water from each set of machines (except the last set) to the grading tank for the next succeeding set of machines.

4. In combination in grinding apparatus, a series of sets of grinding machines, means for carrying sheet glass continuously beneath the series of machines. a series of gradingtanks, one for each set of machines, means for causing an upward flow of liquid through each of the tanks to grade the abrasive therein, means for supplying the graded abrasive from each tank to its set *of grinding machines, means for supplying neat-h the series of machines, a series of grading tanks. one for each set of machines, means for causing an upward flow of liquid through each of the tanks to grade the abrasive therein, means for supplying the graded abrasive from each tank to its set.

of grinding machines, means for supplying the used abrasive and water from the first set of grinding machines to the tank for the next set of machines, and means for returning the abrasive too coarse for use with the second set of machines to the tank for the first set.

6. In combination in grindin apparatus, a series of sets of grindingmac ines', means for carrying sheet glass continuously beneath the series of machines, a series of grading tanks, one for each set of'machines, means for causing an upward flow of liquid through each of the tanks to grade the abrasive therein, means for su plying the graded abrasive from each tank to its set of grinding machines, means for supplying the used abrasive and water from each set of machines (except the last set) to the grading tank for the next succeeding set, and means for returning the abrasive too coarse for use from each tank after the first one to the next preceding tank.

In testimony whereof, I have hereunto subscribed my name this 18th day of July,

JACOB sonnnnnnc. 

